Patching the Shellshock/Bash shell bug or vulnerability ( for Ubuntu 12.04 at least )

Good Lord! Blimey! The Shellshock/"Bash shell" bug seems to be more worrisome than the Heartbleed affair.
Therefore, time to patch up our systems (including this site!)

Wait, check first if your system is affected ( 99% sure I guess ). Tested on GNU bash, version 4.2.25(1)-release-(x86_64-pc-linux-gnu) .